The equation for the chemical reaction shown below is not balanced. What number should replace the question mark to balance this equation? 2Al + ? Cl2 → 2AlCl3 A. the number 2 B. the number 3 C. the number 4 D. the number 5

What is the quantum number set of the ground-state electron that is found in helium (He) but not in hydrogen (H) ? (1, 0, 0, - ½) (1, 0, 1, - ½) (1, 1, 0, - ½) (1, 1, 1, - ½)

How is earths moon different from the moons of other planets

Is jelly beans substance

What conversion process takes place in an electrolytic cell? A.) chemical energy is converted to electrical energy. B.) electrical energy is converted to chemical energy. C.) electrons converted to ions. D.) ions converted to electrons. E.

How many carbon atoms are in 7.05 moles of pyridine

Ammonia (NH3) burns in air to form nitrogen dioxide and water. Calculate grams of nitrogen dioxide produced if 4.0 grams of ammonia are consumed

What year did mendeleev organized his periodic table in order of increasing atomic number

What is the volume of 1.9 moles of chlorine gas (Cl2) at standard temperature and pressure (STP) ? 12 L 22.4 L 43 L 81 L

This decomposition is first order with respect to phosphine, and has a half‑life of 35.0 s at 953 K. Calculate the partial pressure of hydrogen gas that is present after 70.5 s if a 2.20 L vessel containing 2.

A new element has two isotopes, one with a mass of 40.0 amu and the other with a mass of 42.0 amu. the atomic weight is 40.50 g/mol. pick the true statement a. the isotope at 42.0 amu is less abundant b. the element has 19 protons and 21 neutrons c.